27129997440 has 1152 divisors, whose sum is σ = 121417470720. Its totient is φ = 5643509760.

The previous prime is 27129997423. The next prime is 27129997459. The reversal of 27129997440 is 4479992172.

27129997440 is a `hidden beast` number, since 27 + 1 + 2 + 99 + 97 + 440 = 666.

It is a tau number, because it is divible by the number of its divisors (1152).

It is a super-2 number, since 2×27129997440² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 382112605 + ... + 382112675.

It is an arithmetic number, because the mean of its divisors is an integer number (105397110).

Almost surely, 2^27129997440 is an apocalyptic number.

27129997440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 27129997440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (60708735360).

27129997440 is an abundant number, since it is smaller than the sum of its proper divisors (94287473280).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

27129997440 is an frugal number, since it uses more digits than its factorization.

27129997440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134 (or 101 counting only the distinct ones).

The product of its (nonzero) digits is 2286144, while the sum is 54.

The spelling of 27129997440 in words is "twenty-seven billion, one hundred twenty-nine million, nine hundred ninety-seven thousand, four hundred forty".